Automatic printer



March 1, 1960 MacDONALD ErAL AUTOMATIC PRI TER Filed May 20. 1957 4Sheets-Sheet l INVENTORS.

INVENTORS.

4 Sheets-Sheet 2 AUTOMATIC PRINTER D. N. M DONALD ETA]- QQQEQ A March 1,1960 Filed May 20, 1957 Match 1, 1960 D. N. MacDONALD ETAL AUTOMATICPRINTER 4 Sheets-Sheet 3 Filed May 20, 1957 mwefl m 0N5 r v; 0 W W Mm JM m Mm. m:

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AUTOMATIC PRINTER Filed May 20, 1957 4 Sheets-Sheet 4 4 V fn iz VAUTOMATIC PRINTER Duncan N. MacDonald, Arcadia, and Edward L. Glaser,Altadena, Calif., assignors to Burroughs Corporation, Detroit, Micln, acorporation of Michigan Application May 20, 1957, Serial No. 660,318

Claims. (Cl. 101-93) This invention relates to printing machines and,more particularly, is concerned with a high-speed tabulating device forprinting alphanumerical information.

Printing machines for tabulating information, such as derived from acomputer, for example, are well known. Such printing machines can begenerally classified as one of two types. In the series type, onecharacter is printed at a time, successive characters being printeduntil a complete line is made, at which time another line is started.The ordinary typewriter forms a basis of a printing machine of thistype. In the parallel type, a complete line of characters is printed outsimultaneously in the manner of the familiar adding machine. Printingmachines which are a hybrid of these two types also have been developedin which groups of characters but not complete lines of characters areprinted out during each print cycle.

Printing machines of the series type are generally simpler inconstruction and simpler in the circuitry required to control them fromthe input information. However, printing rates for the series typeprinting machine are relatively low. Printing machines of the paralleltype can be operated at very much higher speed by printing out completelines during each print cycle. However, their mechanism is much morecostly and complex and generally the control circuitry is complicated bythe requirement of a memory arrangement by which a complete line ofinformation can be stored at a time.

The present invention is generally classed as a seriestype printmachine, although in one embodiment it may be considered aseries-parallel type machine. It is characterized by its relativesimplicity, ruggedness, and low cost of construction and operation.Although it is a series-type printing machine, it is capable of printingspeeds which are considerably in excess of known seriestype printers,although still not as fast as is achieved by some parallel-typeprinters. Thus, the present invencost.

The present invention achieves these results by means of a novelprinting arrangement which in essence consists of a cylindrical typewheel having type characters arranged around the outer circumference inthe form of a helix. The type wheel is continuously rotated and at thesame time is advanced across the face of theprinting medium along itsaxis of revolution by an amount equal to the pitch of the helix witheach revolution of the type wheel. Thus, each of the type characters inone turn of the helix is brought opposite a fixed point on the printingmedium during one revolution of the type wheel. Successive revolutionsof the type wheel bring each of the type characters opposite other fixedpoints along a line, the points being spaced by an amount equal to thepitch of the helix. A print bar extends in back of the printing mediumand strikes a character on the type wheel through the printing medium toprint out selected characters in response to the input information.

tion provides moderate printing speed at relatively low.

For a better understanding of the invention, reference should be had tothe accompanying drawings, wherein:

Fig. 1 is a plan view of the printer according to the present invention;

Fig. 2 is a sectional view taken substantially on the line 2-2 of Fig.1;

Fig. 3 is an end view looking at the right-hand end of the printer asshown in Fig. 1;

Fig. 4 is a schematic showing of the commutator assembly and controlcircuit associated with the printer of Fig. 1;

Fig. 5 is a fragmentary plan view of a modified version of the printerof Fig. 1;

Fig. 6 is a sectional Fig. 5; and

Fig. 7 is a schematic block diagram of a suitable view taken on the line6-6 of control circuit for use with the modified version of the printerof Figs. 5 and 6.

Referring in particular to Figs. 1-3, the numeral 10 indicates generallythe main frame of the printer, the main frame including a pair of spacedparallel side plates 12 and 14. Journaled in the side plates 12 and 14is a rotatable keyed shaft 16 on which is carried a type wheel 18. Thetype wheel 18 is arranged to slide along the shaft 16 in the directionof the axis of rotation, but

by virtue of a key 20 engaging key slots in the shaft 16 and in the typewheel 18, rotational movement is imparted to the type wheel 18 byrotation of the shaft 16. In the embodiment shown in Figs. 1-3, the typewheel 18 is provided around its periphery with raised type charactersrepresenting the numerals 0 through 9 and the sign characters and Thetype characters are arranged around the outer periphery of the typewheel 18 in a single helical turn.

To rotate the shaft 16 and the associated print wheei 18, a suitablemotor 22, mounted on the main frame 10, drives the shaft 16 through abelt drive, for example. To this end a belt pulley 24 is secured to oneend of the shaft 16, a suitable fiat belt 26 extending between the shaftof the motor 22 and the belt pulley 24.

Axial movement of the type wheel 18 is achieved by means of a bracket 28having arms 29 extending on either side of the type wheel 18 by means ofwhich the type wheel maybe urged along the shaft 16 in an axialdirection. ;The bracket 28 is slidably supported by means of a fixedshaft 30 secured at its ends in the side plates 12 and 14 of the mainframe 10. By means of openings in the ends of the arm portions 29 of thebracket 28 through which the shaft 16 passes, the bracket 28 is alsoslidably supported by the shaft 16.

Movement is imparted to the bracket 28 by means of a flat steel band 32.One end of the flat steel band 32. is

' wound on a spring-loaded drum assembly, indicated generally at 34, bymeans of which tension is applied to the steel band 32. for urging thebracket to the left as viewed in Fig. 1.

The other end of the steel band 32 is secured to a drum 36, the drum 36when rotated drawing the bracket 28 to the right, as viewed in Fig. 1,against the action of the spring-loaded drum assembly 34. The drum 36 isrotatably supported by a vertical shaft 38 journaled at its ends insuitable brackets 40 secured to the outer surface of the I end plate 14.A worm wheel 42 is journaled on the shaft 38, the worm wheel 42 beingrotated by a worm gear 44 on the end of the shaft 16, whereby rotationof the shaft 16 imparts rotation to the worm wheel 42.

To rotate the drum 36 in one direction from the worm wheel 42, a clutcharrangement is provided which includes a driving member 46 which isfeathered or keyed to the shaft 38 and engages a mating driven member 48integral with the worm wheel 42. A spring 50 urges the driving memberinto engagement with the mating member 48. The clutch is disengaged by arunner 52 engaging an annular groove in the driving member 46. Therunner 52 is actuated by a solenoid 54 through suitable linkage wherebyenergization of the solenoid 54 disengages the clutch. This permits thedrum 36 to rotate freely, whereby the bracket 28 may be returned to itsleft hand position by the action of the spring-loaded drum assembly 34.

The diameter of the drum 36 and the gear ratio of the worm driveimparting rotation thereto from the shaft 16 are designed to advance thebracket 28 and associated type wheel 18 a distance equal to the pitch ofthe helix formed by the type characters on the type wheel with eachcomplete revolution of the shaft 16. By this means it will be seen thatthe type characters in effect thread themselvespast a fixed point duringeach revolution of the shaft 16, the fixed points during successiverevolutions of the shaft 16 being spaced parallel to the axis ofrotation thereof a distance equal to the pitch of the helix.

The solenoid 54 is actuated by means of a microswitch 56 mounted on theinside of the end plate 14. A lug 58 secured to the bracket 28 engagesthe microswitch 56 when the bracket 28 reaches the right hand extent ofits travel. Actuation of the microswitch 56 energizes the solenoid 54from a suitable electrical energy source (not shown) thereby disengagingthe clutch and permitting the bracket 28 and type wheel 18 to return tothe left hand extent of their travel.

It should be noted at this point that a positive-acting clutch isprovided, preferably of the type having engaging V grooves as shown inFig. 3. The angular spacing between the V grooves is to the angularrotation imparted to the clutch with one revolution of the shaft 16.This insures that when the clutch engages, the same relationship betweenthe rotational position of the type wheel 18 and the axial positionthereof is maintained. By this means, characters printed in successivelines always fall directly below each other in vertical columns.

Printing is done on a suitable printing medium, such as a strip of paper60 (see Fig. 2). The paper is advanced downwardly by means of a pair ofpaper feed rolls 62 between which the paper passes. The paper feed rolls62 are preferably rotated by a solenoid 64 which advances the paper inincremental steps through a ratchet and pawl linkage as indicatedgenerally at 66 in Fig. 3. The solenoid 64 is connected in series withthe solenoid 54 so that the paper is advanced each time the print wheelcompletes a line and is returned to its initial left hand position. pairof guide shafts 68 extending between the side plates 12 and 14 of theframe that supports rollers 69. To effect printing on the paper 60,print actuating means is provided which includes a printing bar 70extending the width of the paper on the opposite side of the paper fromthe type wheel 18. The printing bar 70 is supported at its ends by apair of bell-crank arms 72 and 74 which are respectively pivotallysupported, as indicated at 76, to

. the side plates 12 and 14 of the frame 10. The opposite ends of thebell-crank arms 72 and 74 are respectively linked to a pair of solenoids78 and 80. Suitable spring means, such as indicated at 82, normallyholds the print bar 70 in spaced relationship with respect to the typewheel 18.

A printing ribbon, such as indicated at 83, is fed between 21 pair ofribbon reels 84 and 86 secured to the end plates 12 and 14 by suitablebracket means 88 and 90. The reels may be spring loaded to hold theribbon in tension, and the reel 84 may be provided with overrunningclutch means which permit the ribbon to advance only from the reel 86 tothe reel 84. The ribbon is supported in the space between the type wheel18 and the paper 60 by a pair of spring guide clips 92 and 94 secured tothe respective arms 29 of the bracket 28. The spring clips preferablygrip the ribbon tightly enough to withdraw The paper is preferablythreaded between a 4 ribbon from the reel 86 during the return of thetype wheel 18.

Thus, when the solenoids 78 and are energized, the print bar '70 pressesthe paper 60 and the ribbon 83 against a type character on the typewheel 18 which is at that instant directly opposite the type bar 70.With proper timing of the energization of the solenoids 78 and 80, anyselected one of the type characters can be printed out while the typewheel 18 is continuously rotated. A whole line of type is generated byactuating the type bar 70 once during each successive revolution of thetype wheel 18, whereby a series of type characters are printed out atintervals on the paper corresponding to the pitch of the helix formed bythe type characters on the type wheel 18.

The solenoids 78 and 80 are controlled in response to information fed tothe printer. One suitable control circuit is shown in Fig. 4 forprinting out decimal characters. Synchronization with the rotation ofthe type wheel 18 is achieved through a commutator indicated generallyat 96 mounted on the outer face of the end plate 12 and rotated by theshaft 16. The commutator includes an insulating plate 98 having a seriesof equally spaced contacts 100, the contacts being angularly spaced thesame amount as the type characters on the periphery of the typewheel'18. The corresponding type characters are indicated in Fig. 4 bythe numerals 0 through 9 and the sign characters and One contact,indicated at 102, has a corresponding blank space on the periphery ofthe type wheel 18.

A rotary contact arm 104 is secured to the shaft 16 and rotated thereby.The arm 104, as it is rotated, successively engages the contacts and102. A suitable slip ring arrangement, including a brush 106 and ring107 insulated from the shaft 16 completes an electrical circuit betweenthe contact arm 104 and a source of potential 108. Pulses are therebyformed as the arm 104 successively engages the contacts of thecommutator.

Assuming, for example, that the printer is to be used in' combinationwith a source of binary-coded decimal digits received in the form ofD.C. levels, as from an electronic computer, paper tape or magnetic tapereaders, or the like, such levels are applied to four and gates 110.Each of these and gates is connected to the blank contact 102 of thecommutator 96. Once each revolution of the shaft 16 a pulse is producedas the circuit is momentarily completed between the potential source 108and the contact 102. This pulse gates open the and gates 110 therebytransferring the D.C. levels representing the binary-coded digitalinformation to the respective four triggers forming a counter 112. Thecounter 112 is a conventional binary type counter made up of triggercircuits and is arranged to be counted down by a series of input pulses.

All of the contacts 100 of the commutator 96 are connected in series tothe counting pulse input of the counter 112. Thus as the arm 104 of thecommutator 96 is rotated past successive contacts, a series of pulsesare generated which are applied to the counter 112. The counter isarranged to count down and produce an output carry pulse when it passesthrough zero. The output carry pulse from the counter 112 is applied tothe type actuator solenoids 78 and 80.

It will be appreciated from the above description that by means of thecontrol circuit of Fig. 4, the solenoids are actuated in response to theinput digit information stored in the counter 112, since the commutatormust rotate through a number of contact positions equal to the numberstored in the counter 112 before an output pulse is generated foractuating the type bar 70. For example, if the binary-coded decimaldigit 5 is stored in the counter 112, the shaft 16 must rotate thecommutator arm 104 past six contacts to the contact corresponding withthe type character 5 on the type wheel. These six pulses count thecounter 112 back to 0, producing an output pulse when the commutator arm104 engages the contact 100 corresponding to thetype character positionAt this instant the type bar 70 is of the type wheel. actuated, therebytyping out the number 5 on the surface of the paper 60. I

The printer and associated control circuit as thus far described areparticularly suited to the printing of numeric information. Wherealphanumeric information is to be printed, a modification of the printeris desirable, as hereinafter described in connection with Figs. 5-7.While the printer as above described may be used for alphanumericinformation by enlarging the type wheel to provide all the necessarycharacters in one helical turn, the speed of operation is adverselyaifected, since the speed of the moving type past the print bar is theprincipal limiting factor in the printing rate.

In the modified version as shown in Fig. 5, a printing wheel 118 isprovided in which the alphanumeric type characters are spaced around theouter periphery of the type wheel in four helical turns, therebyproviding for four times as many type characters as in theabove-described arrangement using a single helical turn of typecharacters. In place of the single type bar 70, four type bars 120,122,124, and 126 are arranged in a quadrant, as best shown in Fig. 6.The upper two print bars 120 and 122 are supported at their ends bysuitable bell-crank arms 123 and 139 respectively, which are pivotallysecured to the end plates 12 and 14 of the main frame 1% at common pivotpoints 132. The bell-crank arms 128 and 1910 project in oppositedirections and are linked to separate pairs of actuating solenoids 134and 136 respectively. Similarly, the two lower type bars 124 and 126 areactuated by separate pairs of solenoids 138 and 140 respectively throughsuitable pivoted bell-crank arms 142 and 144. It will be understood thattwo solenoids are provided for each type bar at either end thereof, asin the previously described printer arrangement.

Each of the four type bars is provided with a plurality of spacedhammers; 141, 143, 145, and 147 indicate the hammers associatedrespectively with the four type bars 120, 122, 124, and 126. Thedistance between the hammers 141 associated with the type bar'120 isequal to four times the pitch of the helix formed by the type characterson the wheel 118. The hammers 143, 145, and 147 are respectively spacedthe same distance on the other three type bars but are arranged ininterlacing relationship such that the space between adjacent hammers isequal to the pitch of the helix. Thus with any given position of thetype wheel 118, four different characters can be printed out byactuating means associated with the four printing bars.

Tooperate the modified printer described in connection with Figs. 5 and6, a six-bit parallel alpha code is preferably used in which charactersare represented by a fourbit binary-coded decimal numeric digit and atwo-bit binary-coded decimal zone digit for each alphanumeric character.A suitable control circuit for operating the printer in response toalphanumeric information received serially from a digital source isshown in Fig. 7. The sixbit coded characters are fed to suitablefour-place registers, the two-bit zone register being indicated at 146,and the four-bit numeric register being indicated at 148. The bits ofsuccessive characters are shifted in serially into the registers 146 and148 by shifting pulses derived from a commutator identical to thecommutator 96 of Fig. 4, and more specifically derived from the contact1112 of the commutator 96 whereby one shifting pulse is received foreach revolution of the type wheel 118. The shifting pulses may also befed back to the digital information source to synchronize the shiftingout of information from the source with the shifting in of informationto the control circuit of Fig. 7.

The register 146 comprises eight trigger circuits which are arranged tostore the two binary bits of each of four binary-coded decimal digitsrepresenting the zone information of the corresponding four"alphanumeric charae ters from the information source. Any one of fourdifferent decimal digits is thereby stored in each of the foursuccessive positions of the zone register 146. Four and gates 150, 152,154, and 156 are provided which are connected respectively to the pairsof triggers forming each of the four storage positions in the register146. The and gate 150 is arranged to be gated open when a binary-codeddecimal digit 0 is stored in the first position of the zone register146. Similarly the gates 152, 154, and 156 are arranged to be gated openwhen the binary-coded decimal digits 1, 2, and 3 are respectively storedin the second, third, and fourth positions of the zone register 146.Each of the and gates is also connected to the contacts of thecommutator 96, whereby pulses are passed by the particular and gateswhich are gated on by the zone register during any one revolution of thetype Wheel 118. The pulses passed are in synchronism with the advancingof the type characters past the type hammers.

The numeric register 148 comprises four binary counters, each of whichis equivalent to the counter 112 of Fig. 4. Each of these counters thusstores one of the binary-coded numeric digits as they are seriallyshifted through the register 148 from the information source. Each ofthe four binary counters forming the register 148 is counted down bypulses passed by the and gates 150, 152, 154, and 156 respectively.Carry pulses are produced by the respective counters when they arecounted down through zero.

The carry pulses from the four counters forming the register 148 arecoupled to the solenoids associated with each of the four type actuatorsof the printer through a commutating stepping switch indicated generallyat 160. The stepping switch 166 is stepped in response to the impulsesfrom the commutator 96 that shift the registers 146 and 148. Thestepping switch 160 includes four poles which are connected respectivelyto the four pairs of type actuator solenoids. The stepping switchadvances through four positions with each successive stepping pulse,contacts of each of the four positions being connected respectively tothe carry pulse outputs of the four counters comprising the register148. Thus as a coded alphanumeric character is successively shiftedthrough the four positions of the registers 146 and 148 in synchronismwith the revolution of the printing wheel 11%, it is associated throughthe stepping switch 160 with the same printing actuator. In this way theproper character isprinted at a given position on the paper during aselected one of four revolutions of the type wheel depending on whichone of the four helical turns of type the character is located.

While operation of the above-described alphanumeric printer is believedevident from the description thereof, a

brief review of the operation follows by way of sum mary. The six-bitcoded information received from the digital source includes abinary-coded numeric zone digit and a four-bit binary-coded decimalnumeric digit. The zone digits, numbering 0 through 3, identifyrespectively the four turns of the helix on the type wheel where theparticular alphanumeric characters are located. The numeric digits,which may have any value up to 0 through 15, identify the angularposition on the type wheel wh re a particular type character is located.As the zone digit advances through the register 146, advancing oneposition for each revolution of the type wheel, it reaches the storageposition in which the value is such as to gate open the associated andgate. Thus if the zone digit were a 0, the and gate would be gated open.With the proper and gate open, pulses are passed to the associatedcounter in the numeric register 148, where the numeric digit of thecoded character is stored. It will be appreciated that the zone digitand the numeric digit of a particular character advance together throughthe four positions of the respective registers 146 and 148. With theassociated and gate open, the counter in the numeric register is counteddown through by a number of pulses corresponding to the value of thenumeric digit stored in the counter. As a result, a carry pulse isgenerated after the type wheel has advanced through a fraction of arevolution so as to bring the appropriate type character identified bythe numeric digit into position opposite one of the hammers. By theaction of the stepping switch, the proper one of the four hammeractuators is connected to the carry output of the respective counters inthe register to print the character in the proper position on the paper.

While one particular arrangement has been described to rotate, advance,and return the type wheel for printing out successive lines, it will beappreciated that other mechanical arrangements are possible forimparting the desired rotational advance to the type characters within apoints along a line parallel to the axis of rotation of the type wheel.Various modifications are possible in the design of the driving circuitsand the commutator also to accommodated difierent coded forms of theinput.

We claim:

1. A tabulator system for printing out alphanumeric information receivedserially in the form of a six bit parallel alpha code including a fourbit binary-coded decimal numeric digit and a two bit binary-codeddecimal zone digit for each alphanumeric character, the tabulator systemcomprising a cylindrical type wheel having a plurality of typecharacters arranged in a helix around the peripheral surface of thewheel, the characters being arranged in spaced relation in four separateturns of the helix, means for rotating the type wheel, means for movingthe type wheel along its axis of rotation by an amount equal to thepitch of the helix with each revolution of the type wheel, four typeactuators, each actuator including a plurality of projecting hammersadapted to Strike the type characters moved into position by rotationand advancing of the type wheel, every fourth hammer being operated bythe same actuator, the spacing between adjacent hammers being equal tothe spacing between adjacent type characters as measured parallel to theaxis of rotation of the type wheel, means responsive to the zone digitsof the coded alphanumeric characters and synchronized with the axialmovement of the type wheel for selecting the hammer actuators to beenergized during a given revolution of the type wheel, and meansresponsive to the numeric digits and synchronized with the rotationalmovement of the type wheel for pulsing the selected actuators at thetime the desired characters pass under the hammers of the selectedactuators.

2. A tabulator system for printing out alphanumeric information receivedserially in the form of a six bit parallel alpha code including a fourbit binary-coded decimal numeric digit and a two bit binary-codeddecimal zone digit for each alphanumeric character, the tabulator systemcomprising a cylindrical type wheel having a plurality of typecharacters arranged in a helix around the peripheral surface of thewheel, the characters being arranged in spaced relation in four separateturns of the helix, means for rotating the type wheel, means for movingthe type wheel along its axis of rotation by an amount equal to thepitch of the helix with each revolution of the type Wheel, four typeactuators, each actuator including hammer means adapted to strike thetype characters, the hammer means of the respective actuators beingspaced at intervals corresponding to the spacing between adjacent typecharacters as measured parallel to the axis of rotation of the typewheel, means responsive to the zone digits of the coded alphanumericcharacters and synchronized with the axial movement of the type wheelfor selecting the hammer actuators to be energized during a givenrevolution of the type wheel, and means responsive to the numeric digitsand synchronized with the rotational movement of the type wheel forpulsing the selected actuators at the time the desired characters passunder the hammer means of the selected actuators.

3. A tabulator system for printing out alphanumeric information receivedserially in the form of a six bit parallel alpha code including a fourbit binary-coded decimal numeric digit and a two bit binary-codeddecimal zone digit for each alphanumeric character, the tabulator systemcomprising a cylindrical type wheel having a plurality of typecharacters arranged in a helix around the peripheral surface of thewheel, the characters being arranged in spaced relation in a pluralityof separate turns of the helix, means for rotating the type wheel, meansfor moving the type wheel along its axis of rotation by an amount equalto the pitch of the helix with each revolution of the type wheel, aplurality of type actuators, equal in number to the number of turns ofthe helix formed by the type characters on the type wheel, each actuatorincluding hammer means adapted to strike the type characters, the hammermeans of the respective actuators being spaced at intervalscorresponding to the spacing between adjacent type characters asmeasured parallel to the axis of rotation of the type wheel, meansresponsive to the zone digits of the coded alphanumeric characters andsynchronized with the axial movement of the type wheel for selecting thehammer actuators to be energized during a given revolution of the typewheel, and means responsive to the numeric digits and synchronized withthe rotational movement of the type wheel for pulsing the selectedactuators at the time the desired characters pass under the hammer meansof the selected actuators.

4. A tabulator system for printing out alphanumeric information receivedserially in the form of a code, the tabulator system comprising a typewheel having a plurality of type characters arranged in a helix aroundthe peripheral surface of the wheel, the characters being arranged inspaced relation in four separate turns of the helix, means for rotatingthe type wheel, means for moving the type wheel along its axis ofrotation by an amount equal to the pitch of the helix with eachrevolution of the type wheel, four type actuators, each actuatorincluding a plurality of projecting hammers adapted to strike the typecharacters moved into position by rotation and advancing of the typewheel, every fourth hammer being operated by the same actuator, thespacing between adjacent hammers being equal to the Spacing betweenadjacent type characters as measured parallel to the axis of rotation ofthe type wheel, and means for operating the actuators at selected timesin response to the serially received coded information.

5. A tabulator system for printing out alphanumeric information receivedserially in the form of a code, the tabulator system comprising a typewheel having a plurality of type characters arranged in a helix aroundthe peripheral surface of the wheel, the characters being arranged inspaced relation in four separate turns of the helix, means for rotatingthe type wheel, means for moving the type wheel along its axis ofrotation by an amount equal to the pitch of the helix with eachrevolution of the type wheel, four type actuators, each actuatorincluding hammer means adapted to strike the type characters, the hammermeans of the respective actuators being spaced at intervalscorresponding to the spacing between adjacent type characters asmeasured parallel to the axis of rotation of the type wheel, and meansfor operating the actuators at selected times in response to theserially received coded information.

6. A tabulator system for printing out alphanumeric information receivedserially in the form of a code, the tabulator system comprising a typewheel having a plurality of type characters arranged in a helix aroundthe 9 peripheral surface of the wheel, the characters being arranged inspaced relation in a plurality of separate turns of the helix, means forrotating the type wheel, means for moving the type wheel along its axisof rotation by an amount equal to the pitch of the helix with eachrevolution of the type wheel, a plurality of type actuators, equal innumber to the number of turns of the helix formed'by the type characterson the type wheel, each actuator including hammer means adapted tostrike the type characters, the hammer means of the respective actuatorsbeing spaced at intervals corresponding to the spacing between adjacenttype characters as measured parallel to the axis of rotation of the typewheel, and means for operating the actuators at selected times inresponse to the serially received coded information.

7. A tabulator system for printing out information received serially inthe form of a code, the tabulator system comprising a type wheel havinga plurality of type characters arranged in a helix around the peripheralsurface of the wheel, the characters being arranged in spaced relationin a plurality of separate turns of the helix, means for rotating thetype wheel, means for moving the type wheel along its axis of rotationby an amount equal to the pitch of the helix with each revolution of thetype wheel, a plurality of actuators, each actuator including hammermeans adapted to strike the type characters, the hammer means of therespective actuators being spaced at intervals corresponding to thespacing between adjacent type characters as measured parallel to theaxis of rotation of the type wheel, and means for operating theactuators at selected times in response to the serially received codedinformation.

8. A tabulator system for printing out information received serially inthe form of a code, the tabulator system comprising a type wheel havinga plurality of type characters arranged in a helix around the peripheralsurface of the wheel, the characters being arranged in spaced relationalong the helix, means for rotating the type wheel, means for moving thetype wheel along its axis of rotation by an amount equal to the pitch ofthe helix with each revolution of the type wheel, hammer means adaptedto strike the type characters at spaced positions parallel to the axisof rotation of the type wheel as the wheel advances, the hammer meansbeing spaced at intervals corresponding to the spacing between adjacenttype characters as measured parallel to the axis of rotation of the typewheel, and means for operating the hammer means at selected times inresponse to the serially received coded information.

9. In a printer, means for supporting a record medium upon which it isdesired to print at a plurality of positions spaced along a line on themedium, a circular member having a plurality of different printingcharacters arranged in a helix around the periphery of the member, thecharacters being arranged in spaced relation in a plurality of separatehelical turns, means mounting the member so that its axis extendsparallel to the line of printing positions on the record medium and sothat it is rotatable about its axis and bodily movable therealong, meansfor continuously rotating the member about its axis and for continuouslybodily moving the member along its axis of rotation as it rotates, theaxial movement of the member being so related to its rotational movementand the helical formation of the printing characters around theperiphery of the member that all of the printing characters successivelythread past each of the printing positions of the record medium andmeans positioned opposite the circular member for effecting simultaneoustransfer of one or more print characters from selected ones of theseveral turns of the helix as the characters are threaded past theprinting positions.

10. An automatic printer for printing characters on a printing mediumcomprising a main frame, a type wheel having a plurality of typecharacters arranged in a plurality of helical turns around the outerperiphery of the type wheel, means for rotating the type wheel, meansfor advancing the type wheel in one direction along its axis of rotationa distance equal to the pitch of the helix with each complete revolutionof the wheel, means for returning the type wheel in the oppositedirection along its axis of rotation at a high rate of speed after thewheel has been advanced to the limit of its travel by said advancingmeans, means supported by the main frame for movably supporting theprinting medium in spaced but substantially tangential relationship tothe outer periphery of the type wheel as it rotates, means synchronizedwith said type wheel returning means for advancing the printing medium apredetermined amount in a direction at right angles to the axialdisplacement of the type wheel each time the type wheel is returned, anda plurality of separately actuatable means for selectively engaging theprinting medium with type characters in any one of the plurality ofhelical turns during one revolution of the type wheel.

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